Research on Antarctic Coastal Ecosystem Rates (RACER): Mechanisms of Bloom Formation and Decline

来自南极半岛沿海地区研究的历史数据和观测提供了大量浮游植物大量繁殖的详细文件，这些浮游植物大量繁殖发生在Gerlache海峡和Bransfield海峡的西南部分。水文资料表明，在水华形成区域，流场是相对静止的。所提出的工作的目标是了解有关导致这些华的形成和下降的机制的时间细节。南极海岸生态系统速率研究（RACER）项目的这一组成部分将利用跨学科的方法来解决浮游植物对物理强迫的反应。重点将放在上层水柱湍流混合的高时间分辨率的气象强迫和浮游植物的响应上。这将通过在靠近主站的岛屿上建立一个永久气象站和快速分析物理-光学-生物特性来完成。将进行浮游植物速率过程的详细研究，包括碳和氮同位素吸收研究，叶绿素a的放射性碳标记确定的生长速率以及光适应动力学。浮游植物的光适应状态将从光学、生化和光合参数来确定。这些信息对于理解水华形成的潜在机制是必不可少的。这种理解对于开发能够预测自然环境强迫的季节进展和年际变率的机制模式是必需的。

Historical data and observations from studies of the coastal Antarctic Peninsula region provide detailed documentation of massive phytoplankton blooms which develop within the Gerlache Strait and the southwest portion of the Bransfield Strait. Hydrographic data indicate that the flow field is relatively quiescent in the region of bloom formation. The objectives of the proposed work are to understand the temporal detail regarding the mechanisms leading to formation and decline of these blooms. This component of the RACER (Research on Antarctic Coastal Ecosystem Rates) program will utilize an interdisciplinary approach to resolve the phytoplankton response to physical forcing. The emphasis will be on high temporal resolution of meteorological forcing of turbulent mixing within the upper water column, and the response of the phytoplankton. This will be accomplished with a permanent meteorological station on an island adjacent to the primary station and rapid profiling of physical- optical-biological properties. Detailed studies of phytoplankton rate processes including carbon and nitrogen isotope uptake studies, growth rates determined by radio-carbon labelling of chlorophyll a, and kinetics of photoadaptation will be carried out. The photoadaptive status of the phytoplankton crop will be determined from optical, biochemical, and photosynthetic parameters. This information is essential for an understanding of the underlying mechanisms of bloom formation. Such an understanding is required for development of mechanistic models which are capable of predicting seasonal progression and interannual variability forced by the physical environment.